A lot of the fics I see really get stuck on the 'stoic loners bonding' thing, which isn't wrong exactly, but it misses the quiet pragmatism of their actual dynamic. They're not two brooding souls finding solace in each other's angst; they're two capable men who communicate through work, not words. The best ones I've read show Charles teaching Arthur survival skills—not just hunting, but the respectful way to do it—and Arthur slowly mirroring that respect for the land and the people on it.
It's less about dramatic confessions and more about the unspoken understanding that builds when you rely on someone to watch your back during a hunt or in a fight. The friendship grows in the space between dialogues, in the shared glance after a job goes sideways, in the way Charles is maybe the only one who calls Arthur out without judgment, and Arthur listens because it's Charles. I think the fandom sometimes forgets how funny they can be together too, that dry, understated humor. The friendship feels most real when it's grounded in the daily grind of camp life, not some epic separation from it.